2 * Copyright (c) 2014 Cisco Systems, Inc. and others. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
8 package org.opendaylight.mdsal.binding.dom.codec.impl;
10 import static java.util.Objects.requireNonNull;
12 import java.lang.invoke.MethodHandles;
13 import java.lang.invoke.VarHandle;
14 import org.eclipse.jdt.annotation.NonNull;
15 import org.opendaylight.mdsal.binding.runtime.api.CompositeRuntimeType;
16 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier.Item;
17 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
19 abstract sealed class CommonDataObjectCodecPrototype<T extends CompositeRuntimeType> implements CodecContextSupplier
20 permits AugmentationCodecPrototype, DataObjectCodecPrototype {
21 private static final VarHandle INSTANCE;
25 INSTANCE = MethodHandles.lookup().findVarHandle(CommonDataObjectCodecPrototype.class,
26 "instance", CommonDataObjectCodecContext.class);
27 } catch (NoSuchFieldException | IllegalAccessException e) {
28 throw new ExceptionInInitializerError(e);
32 private final @NonNull T type;
33 private final @NonNull CodecContextFactory factory;
34 private final @NonNull Item<?> bindingArg;
36 // Accessed via INSTANCE
37 @SuppressWarnings("unused")
38 private volatile CommonDataObjectCodecContext<?, T> instance;
40 CommonDataObjectCodecPrototype(final Item<?> bindingArg, final T type, final CodecContextFactory factory) {
41 this.bindingArg = requireNonNull(bindingArg);
42 this.type = requireNonNull(type);
43 this.factory = requireNonNull(factory);
46 final @NonNull T getType() {
50 final @NonNull CodecContextFactory getFactory() {
54 final @NonNull Class<?> getBindingClass() {
55 return bindingArg.getType();
58 final @NonNull Item<?> getBindingArg() {
62 abstract @NonNull NodeIdentifier getYangArg();
65 public final CommonDataObjectCodecContext<?, T> get() {
66 final var existing = (CommonDataObjectCodecContext<?, T>) INSTANCE.getAcquire(this);
67 return existing != null ? existing : loadInstance();
70 private @NonNull CommonDataObjectCodecContext<?, T> loadInstance() {
71 final var tmp = createInstance();
72 final var witness = (CommonDataObjectCodecContext<?, T>) INSTANCE.compareAndExchangeRelease(this, null, tmp);
73 return witness == null ? tmp : witness;
76 // This method must allow concurrent loading, i.e. nothing in it may have effects outside of the loaded object
77 abstract @NonNull CommonDataObjectCodecContext<?, T> createInstance();